i feel like it’s a little weirdly shaped

It looks so good! Try adding some darker tones in to get it some depth (I recommend using a higher density of pencil)

I’ll teach you a trick I use… take a picture of your drawing and using a photo collage app put the reference and sketch side by side so you can tell the difference and why it’s looking off. I can tell from the canvas that it’s going to be a painting, correct?